The present invention relates to methods of preparing glucosamine hydrochloride from chitin or chitinaceous material.
Glucosamine hydrochloride (GHCl) is an amino sugar which is incorporated into the structure of body tissues. It comprises about 80% glucosamine, a compound helpful in maintaining joint health in individuals suffering from degenerative conditions such as arthritis. When orally ingested, it is selectively taken up by joint tissues to exert beneficial effects. Glucosamine may also have other therapeutic effects such as antiviral, anti-cancer, anti-aging, immune boosting or cholesterol lowering activity.
GHCl may be obtained by hydrolysis and deacetylation of chitin, a polymer of N-acetyl glucosamine or by the hydrolysis of chitosan with hydrochloric acid. It is desirable if such processes are efficient in both time and cost, and produce high-purity product with good yield. As well, it would be advantageous to provide a quick, simple and accurate method of assaying GHCl to be used in conjunction with a method of producing GHCl.
The present invention is directed to a method of producing glucosamine hydrochloride from chitin or chitinaceous material, said method comprising the steps of: (a) grinding the chitin or chitinaceous material to less than about xe2x88x9220 mesh; (b) digesting the chitin with prewarmed, concentrated HCl, by mixing the chitin with the HCl, and heating to about 95xc2x0 C. to produce a slurry; (c) cooling the slurry to room temperature and filtering the precipitate; (d) dissolving the precipitate in water and with activated charcoal at room temperature; (e) filtering the solution and discarding the solids; (f) evaporating the solution to recover GHCl solids; (g) washing the solids with ethanol and filtering the solids/ethanol mixture to separately recover both the solids and the ethanol; and (h) drying the solids.
In another aspect, the invention may comprise a method of producing glucosamine hydrochloride from chitin or chitinaceous material, said method comprising the steps of: (a) hydrolysing the chitin in hydrochloric acid; (b) precipitating the glucosamine hydrochloride; (c) separating the precipitated glucosamine hydrochloride and redissolving it in water; and (d) assaying for GHCl by pHmetric titration.
In another aspect, the invention may comprise a method of assaying GHCl in solution comprising the step of measuring the amount of base necessary to raise the pH of the solution to a pre-determined value and corresponding the amount of base to an amount of GHCl. The base may be sodium hydroxide.